Trial Requested for Covid-19 Vaccine Nasal Spray

(Pixy.org)

27 Nov. 2020. Makers of a Covid-19 vaccine given as a nasal spray asked the Food and Drug Administration to authorize a a human clinical trial of the vaccine. In the request to FDA, Altimmune Inc. in Gaithersburg, Maryland cites a preclinical study of its AdCovid vaccine with lab mice conducted by researchers at University of Alabama in Birmingham.

Altimmune is a developer of drugs that invoke the immune system, including vaccines against infectious diseases. Among the company’s pipeline products is NasoVax, an influenza vaccine formulated as a nasal spray that Altimmune says in clinical trials generates protective antibodies as well as injected flu vaccines. In addition, says the company, NasoVax protects against infections in mucous membranes and generates T-cell responses in the immune system, with those immune responses lasting 12 to 14 months in about half of the participants.

AdCovid, says the company, is designed using a similar technology as NasoVax to produce multiple immune responses. The vaccine’s chemistry resembles receptor proteins in cells, where the SARS-CoV-2 virus’s spike protein binds, to begin the infection process. When binding to the spike protein, AdCovid aims to generate immunoglobulin G and A, or IgG and IgA, neutralizing antibodies in the blood and mucous membranes respectively, to prevent immediate Covid-19 infections, but also prevent infections from developing in the respiratory tract.

A team at Alabama-Birmingham, led by microbiologist Frances Lund, tested AdCovid in lab mice for its ability to produce an immune response. As reported by Science & Enterprise in July, and later submitted for publication, results show AdCovid produces detectable levels of IgG antibodies in mice 14 days after a single dose. After 28 days, say the researchers, AdCovid generates a concentration of antibodies at twice the level than recommended by FDA for convalescent plasma, donated by individuals who recover from Covid-19 infections.

In addition, a single dose of AdCovid produces IgA antibodies in mouse respiratory fluids in mucous membranes at levels 29 times higher than before vaccination, and well above IgA antibody levels produced in other vaccines designed to act in mucosal tissue. Lund notes in a university statement that “nasal mucosal immunity may be essential in preventing the spread of the SARS-CoV-2 virus to other individuals by stopping replication and transmission of the virus at the site of infection, the nose and respiratory tract.”

“AdCovid has the potential to provide many benefits not offered by current vaccines,” says Altimmune’s CEO Vipin Garg in a company statement, “including simple intranasal administration, particularly well-suited for use in children, the ability to be transported at room temperature and conveniently stored in refrigerators for years, and the stimulation of nasal mucosal immunity with the potential to provide sterilizing immunity and block transmission of the SARS-CoV-2 virus.”

The request to FDA is an investigational new drug application, in effect, a request to begin clinical trials. Altimmune reports that in an initial meeting with FDA, the agency agreed to the company’s design for a phase 1 or early-stage clinical trial of AdCovid, including the planned population for recruiting participants, as well as vaccine manufacturing plans. The company also says FDA noted earlier toxicology studies of Altimmune’s other nasal spray vaccines removed the need for separate toxicity tests for AdCovid.

More from Science & Enterprise:

• Infographic – Vaccines Boost Biotech Shares
• Covid-19 Vaccine Shown Effective, Temperature-Stable
• Trial Shows Covid-19 Vaccine Safety, Immune Response
• Inhaled Dry-Powder Covid-19 Antibodies in the Works
• 200M Covid-19 Vaccine Doses Donated to Int’l Effort

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